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I heard rumblings of this a few months back since adidas took over Yeezy Supply this year. It looks like its official and adidas has finally switched over the YS check out process from Shopify to Demandware which is what they use on adidas.com.
This obviously greatly changes the set up and planning for future YS drops. Just as Shopify was eliminating bots we have adidas switch to a platform that I’m not convinced is as human user friendly. Will keep an eye on this and report back when I have more info.